Expandable conduit-guide and a method for applying and positioning an expandable conduit-guide

ABSTRACT

The invention relates to an expandable conduit-guide ( 1 ) providing a leak-tight conduit through a skin ( 3 ) between an inside of a corpus ( 2 ) and an outside of the corpus ( 2 ). Said conduit-guide ( 1 ) includes a body ( 100 ) encompassing a lumen ( 110 ) extending essentially axially along a center-line ( 120 ), and has a distal-end ( 130 ) to be positioned outside of the corpus ( 2 ), and a proximal-end ( 140 ) to be positioned inside of the corpus ( 2 ), so that a medical device ( 4 ) can be placed in and passed through the lumen ( 110 ) between the distal-end ( 130 ) and the proximal-end ( 140 ). The body ( 100 ) of the conduit-guide ( 1 ) is constructed from a braided-wire ( 150 ) so that the conduit-guide ( 1 ) is capable of actively expanding from a closed diameter (D 1 ) to an opened diameter (D 2 ) with the placement of the medical device ( 4 ) positioned within the lumen ( 1 10 ) and passively collapsing from the opened diameter (D 2 ) to the closed diameter (D 1 ) upon withdrawal of the medical device ( 4 ) under a spring load of the braided-wire ( 150 ). The invention is also related to a catheter-sheath ( 8 ) and a catheter-sheath-assembly ( 800 ) as well as to a method for applying and positioning an expandable conduit-guide ( 1 ), catheter-sheath ( 8 ) and a catheter-sheath-assembly ( 800 ) in accordance with the present invention.

This application claims the priority of Provisional patent applicationNo. 60/788,366, filed Mar. 30, 2006, the disclosure of which isincorporated herein by reference.

The invention relates to an expandable conduit-guide, a catheter-sheath,a catheter-sheath-assembly and a method for applying an expandableconduit-guide, a catheter-sheath and a catheter-sheath-assembly inaccordance with the preamble of the independent claim of the respectivecategory.

This disclosure provides a means to enable percutaneous access for amedical device, in particular to exchange cannulae positioned in theheart and/or major vessels and/or other organs utilized forextracorporeal communication of fluid or diagnostic/therapeutic devices.The device proposed by the present invention provides a conduit-guidecommunicated between the fluid supply extending outside of the body. Theconduit-guide enables the passage of a medical device, in particular ofa cardiac cannula in and out of the body while effecting a fluid sealduring the exchange.

Medical devices such as cardiac cannulae or other medical devices aretypically placed under direct vision into major blood vessels and/or theheart of a patient for the purpose of providing a fluid conduit to andfrom an extracorporeal circuit.

The most common techniques used in Cardiac Surgery Centers forpostcardiotomy support include Extracorporeal Membrane Oxygenation(ECMO) and Ventricular Assist Devices (VAD). Poor ventricular functionmay be diagnosed preoperatively or may have resulted from myocardialinsult during surgery (i.e. inadequate perfusion, crossclamping forextended periods of time limiting reperfusion, injury, etc.). Reducedcardiac output will affect other organs due to low blood pressure andblood flow.

Over time, allowing the myocardium to rest may allow recovery.Otherwise, the patient may require long-term cardiac support. Patientswho cannot be weaned from cardiopulmonary bypass and possess isolatedventricular dysfunction are probably candidates for a Ventricular AssistDevice (VAD). BiVAD support will require 2-pump circuits. When pulmonarydysfunction occurs, the patient is most likely a candidate for ECMO.

Cardiac cannulae provide the patient interface means to anextracorporeal blood circuit. Placement of these cannulae may access thevasculature through major vessels (Right Atrium (RA), Left Atrium (LA),Left Ventricular Apex (LVA), Femoral Artery (FA), Femoral Vein (FV),Superior Vena Cava (SVC), Inferior Vena Cava (IVC) or the Aorta. Twocannulae are required in the extracorporeal circuit—one for bloodoutflow and one for blood return.

The blood outflow cannula is passed through a dilated tunnel createdfrom the ventricle through the subcutaneous plane to the percutaneousaccess site. The blood return cannula is passed through a dilated tunnelcreated from the arch of the ascending aorta through the subcutaneousplane to the percutaneous exit site. The percutaneous access sites arelocated ipsilaterally, on the left abdominal wall for the LVAD, in themedial anterior position. The location is ipsilateral on the rightabdominal wall for an RVAD, in the medial anterior position.

The extracorporeal system is attached to the cannulae using goodperfusion technique.

Cannulae placed within the thorax are typically secured in place toprevent accidental dislodgement which could result in a catastrophiccondition, purse-string sutures and stabilizer grommets often providesecurity until tissue healing occurs. As such, cannulae the removaland/or exchange of other medical devices require a second surgery underdirect visualization. The open chest wound is closed upon successfullyadministrating the support system.

A problem, which is up to now not yet solved in a satisfactory way, isthat the medical devices, which must be introduce into and tunnelledthrough the tissue of the corpus of patient to get access to the heart,an associate vessel or to an other organ, very often have acomparatively large diameter and/or may have an inappropriate surface,for example a rough surface. Among further things, both can affect theskin, tissue or the respective organs to be accessed very negatively andcan cause lasting injuries.

It is therefore an object of the invention to provide a device and amethod for tunneling and position a medical device, in particular acardiac cannula, in a corpus of a patient, enabling a very easy accessto an organ in a very conservative manner.

The subject matter of the invention which satisfies these objects ischaracterized by the features of the independent claims of therespective category.

The respective subordinate claims relate to particularly advantageousembodiments of the invention.

The invention thus relates to an expandable conduit-guide providing aleak-tight conduit through a skin between an inside of a corpus and anoutside of the corpus. Said conduit-guide includes a body encompassing alumen extending essentially axially along a center-line, and has adistal-end to be positioned outside of the corpus, and a proximal-end tobe positioned inside of the corpus, so that a medical device can beplaced in and passed through the lumen between the distal-end and theproximal-end. The body of the conduit-guide is constructed from abraided-wire so that the conduit-guide is capable of actively expandingfrom a closed diameter to an opened diameter with the placement of themedical device positioned within the lumen and passively collapsing fromthe opened diameter to the closed diameter upon withdrawal of themedical device under a spring load of the braided-wire.

The Expandable conduit-guide in accordance with the present invention isessentially a wire braided tube covered with a flexible membrane such toeffect a leak-tight conduit-guide capable of actively expanding with theplacement of e.g. a cannula or another medical device positioned withinits lumen and passively collapsing upon withdrawal of the cannula oranother medical device, under spring load and tissue compression.

The conduit-guide is preferably positioned under direct visualization atthe time of the medical device placement during open surgery with theproximal end of the conduit-guide for example positioned in a wall of aheart or major vessel of an human patient or an animal, the body of thedevice tunnelled in the corpus of the patient or the animal and a distalend emerging through the skin to externally communicate the lumen. Thedevice is “normally closed”, that is it has a small closed diameterrequiring minimal tissue puncture due to the small device profile.

Passaging a medical device, e.g. a blood cannula or another medicaldevice through the lumen of the conduit-guide in accordance with thepresent invention, the conduit-guide is actively dilated with thepassage of the medical device through the lumen and into a heart, vesselor another organ of the patient.

Upon removal of the medical device, the heart muscle or the vessel wall,a diaphragm and/or the skin constrict to assist the spring returnconduit-guide to collapse.

That is, using a conduit-guide in accordance with the present invention,allows to apply and position a medical device within an human or ananimal corpus in a very easy and conservative way, because beforepositioning the medical device within the corpus, which medical devicemay have a comparatively considerably diameter and/or may have aninappropriate surface which may affect negatively the tissue and/or theskin and or an organ by tunnelling through, the conduit-guide, having ina closed state a comparatively small closed diameter, is firstpositioned within the corpus of the patient, only requiring a smalltunnel through the skin and the tissue of the corpus due to the smalldiameter of the conduit-guide in the closed state. After havingpositioned the conduit-guide within the corpus, the medical device canbe tunnelled though the conduit-guide in a very conservative mannerbecause the medical device will essentially not get in touch with thetissue and/or the skin during tunnelling and, thus, the corpus of thepatient will nearly not be negative affected by applying and positioningthe medical device within the corpus.

In a special embodiment which is very important in practise, apre-determinable portion of the braided-wire is covered by a flexiblemembrane, which is preferably an elastomeric material creating amembrane-like structure, enabling the braided-wire to articulate fromthe closed diameter to the opened diameter and the flexible membranesealing an interstitial space resultant between the braid openings. Afurther important advantage of the flexible membrane is that theconduit-guide can be tunneled through the skin, the tissue and a wall ofthe heart, the vessel or a wall of a organ of a patient in a veryconservative and easy manner because, due to the flexible membrane, thesurface of the conduit-guide becomes smooth and very tissue-friendly.

Regarding another embodiment of the present invention, in the appliedstate, a pre-determinable velour-portion of the conduit-guide emergingthrough the skin of the corpus, is contained within a velour-like tubeto enable a tissue in-growth of the skin, in particular to reducebacterial wicking about the wound and/or the velour material is knittedand/or woven polyester and/or the velour-portion is bonded as avelour-tube to an outside diameter of the conduit-guide. A knittedmaterial structure will expand and contract more easily than a wovenstructure and would be preferred at the skin site. The velour tube ispreferably bonded to the outside diameter of the conduit-guide.

In a special embodiment, the proximal-end of the conduit-guide includesa bare-section which does not contain the flexible membrane in order topermit tissue in-growth about the braided-wire, in particular to providea means for anchoring the conduit-guide and/or the bare-section rangesfrom 0″ to 0.5″, in particular from 0″ to 0.1″, preferably from 0″ to0.25″ from a proximal tip of the conduit-guide. In case that theproximal end of the conduit-guide will not contain the membrane on theoutside, tissue in-growth is permitted about the wires to provide ameans for conduit-guide anchoring. In the bare-section the individualwire is individually coated. In another embodiment, a coating about theindividual wires may not be present.

A distal wire-end of a conduit-guide in accordance with the presentinvention is closed-ended, in particular closed-ended accomplished by afold of the wire, and/or includes a welded joint end or a coating,especially a polymer coating joining the wire.

The flexible membrane, and/or the closed-ended accomplished by a fold ofthe wire and/or including a welded joint end and/or the coating, and orthe polymer coating joining the wire, is fabricated from polyurethaneand/or vinyl and/or a thermoplastic rubber and/or a natural rubberand/or a thermoset material, in particular silicone and/or the flexiblemembrane is dip molded and /or blown film and/or extruded and/orinjection molded and/or pultruded and or assembled from flat stock as aseparate component and/or assembled to the braided body and/or theflexible membrane is applied about the braided-wire by dipping and/or bycoating the braided-wire with liquid polymer and/or the flexiblemembrane is spray applied to the braided-wire. The preferred materialfor the flexible membrane is silicone resisting complete compression setafter indwelling time in the corpus.

In a un-compressed state, a lumen-diameter of the conduit-guide isbetween 0.1″ and 1″, in particular between 0.25″ and 0.75″, preferablyabout 0.5″ and/or wherein the wire is braided to a loose pitch rangingfrom 0.5″ to 4″, in particular from 0.75″ to 3″, especially from 1 ″ to2″ and/or preferably a target length of the wire is 1.5″ pitch for acompressed diameter and/or wherein in a compressed state thelumen-diameter ranges from 0.03″ to 0.15″, in particular from 0.06″ to0.10″, preferably about 0.08″.

The wire may be braided to a loose pitch ranging from 0.5″ to 4″,preferably ranging from 1″ to 2″ with the target length being 1.5″ pitchfor a compressed diameter.

To avoid misunderstandings, it is noted that the dimension unit 1″ isused in the usual way, that is 1″=1 in=1 inch which equals to 2.54 cm.

The number of wires utilized in the over-under braid, preferably, butnot necessary ranges from 5 to 100 wires, in particular from 20 to 48wires, preferably from 24 to 32 wires and/or wherein about half of thewires being left-hand wind and about half of the wires being right-handwind and/or a wire-diameter of a strand is between 0.001″ to 0.02″, inparticular 0.003″ to 0.01, preferably about 0.005″ and/or the wire ismade of plastic, and/or made of a composite material, and/or made of ametal, especially made of a stainless steel, preferably made of at least½ hard stainless steel.

It is understood that the pitch, wire diameter, number of wires, braidpattern, compressed diameter, and expanded diameter are not limited tothese dimensions and will be a function of tightness of braid resultantdimensions desired, strength of spring rate of the coil and otherimportant parameters.

In a further important embodiment, the conduit-guide in accordance withthe present invention, is pre-assembled at a certain diameter into acatheter-sheath wherein the catheter-sheath may or may not include adepth-marker, in particular a depth-marker-band for positioning aproximal-end of the catheter-sheath in the corpus an human patient or ananimal and/or the catheter-sheath includes a pusher-device for theremoval of the catheter-sheath after positioning the conduit-guidewithin the corpus.

Thus, the conduit-guide in the compressed state is preferablypre-assembled into the catheter sheath. Contained within thecatheter-sheath can also be a pusher-device for sheath removal once theassembly is positioned within the body and the distal end externalized.Placement of the conduit-guide would be performed with thecatheter-sheath in place. It is envisioned that the catheter-sheathwould be placed within the body cavity and the distal end tunnelled toemerge out the desired percutaneous site. Once accomplished, e.g. theheart (or major vessel) would be entered by poking the device throughthe wall. Depth placement for positioning of the proximal end will beidentified by marker bands about the catheter-sheats.

The invention also relates to a catheter-sheath for pre-assembling aconduit-guide as described above in great detail.

In a special embodiment, the catheter-sheath includes a pusher-devicefor removal the conduit-guide after positioning the conduit-guide withinan human or an animal corpus and/or includes a depth-marker, inparticular a depth-marker-band for positioning a proximal-end of thecatheter-sheath in the corpus.

Furthermore, the invention relates to a catheter-sheath-assemblyincluding a catheter-sheath as already described.

The invention relates also to a method for applying and positioning anexpandable conduit-guide within an human or an animal corpus, and/or amethod for positioning a catheter-sheath, and/or a method forpositioning a catheter-sheath-assembly in accordance with the presentinvention, including the following steps:

providing a conduit-guide in accordance with the present invention;

positioning a proximal-end of the conduit-guide in a wall of a heartand/or a major vessel;

tunneling a distal-end of the conduit-guide through a skin of the corpusto externally communicate a lumen of the conduit-guide;

and/or including the following steps:

providing a conduit-guide in accordance with the present invention;

tunneling a distal-end of the conduit-guide through a skin of the corpusto externally communicate a lumen of the conduit-guide;

positioning a proximal-end of the conduit-guide in a wall of a heartand/or a major vessel.

In a special embodiment of a method in accordance with the presentinvention, a medical device is placed in and/or passed through the lumenof the conduit-guide and/or the conduit-guide is actively dilated withthe passage of the medical device through the lumen.

Preferably, on removing the medical device from the conduit-guide, theconduit-guide is collapsed.

In another embodiment of a method according to the present invention,which is very important in practice, the conduit-guide is pre-assembledinto a catheter-sheath forming a catheter-sheath-assembly, wherein,especially, the catheter-sheath-assembly is placed within acorpus-cavity, a distal-end of the catheter-sheath-assembly is tunneledto emerge out the desired percutaneous site of the corpus, a heartand/or an associated vessel, in particular a major vessel is entered bypoking the catheter-sheath-assembly and/or the conduit-guide tunnelledthrough a wall of the heart and/or the associated vessel and/or aproximal-end of the catheter-sheath-assembly and/or of the conduit-guideis positioned by using a depth-marker, in particular adepth-marker-band, provided about the catheter-sheath.

Preferably, but not necessarily, the catheter-sheath includes apusher-device and the catheter-sheath is removed by the pusher-deviceonce the conduit-guide is positioned within the corpus and/or once thedistal-end of the conduit-guide is externalized.

In a further embodiment, the proximal-end of the conduit-guide is fixedby a suture at a wall of the heart and/or of a associate vessel and/orat a tissue of the corpus.

The medical device is preferably a cannula, in particular a cardiaccannula providing a blood conduit between a major blood vessel and/or anexternal device, in particular an Extracorporal Membrane Oxygenationand/or a Ventricular Assist Device and/or a circuit including a bloodpump.

The medical device may also be a scope and/or a light and/or acamera/and/or another medical device and/or the conduit-guide isprovided as a conduit for performing a vision access required fordiagnostic and/or therapeutic applications and/or for multi-purposecatheters with vision and/or for therapeutic device access.

With the method in accordance with the present invention, it is alsopossible to perform an access to a kidney, a bladder, a G.I. tract, inparticular to an intestine, a stomach, or an esophagus, to a thoraxcavity or to a sinus is performed by the guide-conduit.

In the following, the invention will be explained in more detail withreference to the drawings. Shown are:

FIG. 1: an expandable conduit-guide applied within a patient's corpus;

FIG. 2: a cardiac cannula actively expanding a conduit-guide;

FIG. 3: a conduit-guide including a flexible membrane;

FIG. 4: a conduit-guide according to FIG. 3 in the applied statecomprising a velour-portion;

FIG. 5 a: a catheter-sheath-assembly;

FIG. 5 b: a catheter-sheath-assembly according to FIG. 5 a partlyremoved;

FIG. 5 b a catheter-sheath-assembly with the conduit guide beingattached to the wall of a heart.

In FIG. 1 an expandable conduit-guide according to the present inventionbeing applied within a patient's corpus is schematically displayed,which expandable conduit-guide will be designated in the following bythe reference number 1.

The expandable conduit-guide 1 providing a leak-tight conduit through askin 3 between an inside of a corpus 2 and an outside of the corpus 2,includes a body 100 encompassing a lumen 110 extending essentiallyaxially along a center-line 120, and having a distal-end 130 which is inFIG. 1 positioned outside of the corpus 2, and having a proximal-end140, which is in the example of FIG. 1 positioned inside of the corpus 2at a wall 9 of a heart of patient, so that the medical device 4, whichis in the present example a cardiac cannula 4, can be placed in andpassed through the lumen 110 from the distal-end 130 form the outside ofthe corpus 2 via the proximal-end 140 through the inside of the corpus 2and into the heart of the patient to provide a means for a bloodexchange between a chamber of the heart and an external device, e.g. toa blood pump, which is not shown in FIG. 1.

In FIG. 2 the conduit-guide 1 is displayed in more detail to betterexplain the co-operation of the conduit-guide 1 with a medical device 4,such as a cardiac cannula 4 as exemplary shown by FIG. 2. The body 100of the conduit-guide 1 is constructed from a braided-wire 150, so thatthe conduit-guide 1 is capable of actively expanding from the closeddiameter D1 to the opened diameter D2 with the placement of the medicaldevice 4 positioned within the lumen 110. On the other hand, removingthe medical device 4 for from the conduit-guide 1, allows theconduit-guide 1 to passively collapse from the opened diameter D2 to theclosed diameter D1 upon withdrawal of the medical device 4 under aspring load of the braided-wire 150.

That is, using a conduit-guide 1 in accordance with the presentinvention, allows to apply and position the medical device 4 in a veryeasy and conservative way. That's why before positioning the medicaldevice 4 within the corpus 2, which medical device 4 has in most cases acomparatively large diameter or can have an inappropriate surface whichmay affect negatively the tissue or an organ by tunnelling through, theconduit-guide 1, having in its closed state a comparatively small closeddiameter D1, is first positioned within the corpus 2 of the patient. Dueto the small diameter D1 of the conduit-guide 1 in the closed state, theconduit-guide 1 only requires a small tunnel through the skin 3 and thetissue of the corpus 2. After having positioned the conduit-guide 1within the corpus 2, the medical device 4 can be tunnelled to e.g. theheart through the conduit-guide 1 in a very conservative manner becausethe medical device 4 will essentially not get in touch with the tissueand/or the skin during tunnelling and, thus, the corpus 2 of the patientwill not be negative affected by applying and positioning the medicaldevice 4, e.g. a cardiac cannula 4, within the corpus 2.

The embodiment of a conduit-guide 1 shown in FIG. 3 includes a flexiblemembrane 5. Regarding this embodiment, which is very important inpractice, a pre-determinable portion of the body 100 and thebraided-wire 150, respectively, is covered by a flexible membrane 5enabling the braided-wire 150 to articulate from the closed diameter D1to the opened diameter D2 and, additionally, the flexible membrane 5seals an interstitial space 151 resultant between the braid openings.

A very important advantage of a conduit-guide 1 according to FIG. 3having a flexible membrane 5, which is preferably made of an elastomericmaterial creating the membrane-like structure, is that the conduit-guide1 can be tunneled through the skin 3, the tissue and a wall 9 of theheart of the patient, or the vessel, or a wall of a organ in a veryconservative and easy manner because due to the properties of theflexible membrane 5 the surface of the conduit-guide 1 becomes smoothand very tissue-friendly.

In FIG. 4 a conduit-guide 1 according to FIG. 3 is displayed in theapplied state, comprising a velour-portion 6 in a pre-determinableportion of the body 100 of the conduit-guide 1.

In the example of FIG. 4 the pre-determinable velour-portion 6 of theconduit-guide 1 is emerged through the skin 3 of the corpus 2, and iscontained within a velour-like tube 61 to enable a tissue in-growth ofthe skin 3, in particular to reduce bacterial wicking about the wound.Preferably, the velour material is knitted and/or woven polyester andthe velour-portion 6 is bonded as a velour-tube 61 to an outsidediameter of the conduit-guide 1.

The proximal-end 140 of the conduit-guide 1 includes a bare-section 7which is placed in the wall 9 of the heart of a patient. Thebare-section 7 does not contain the flexible membrane 5 in order topermit tissue in-growth about the braided-wire 150. That provides inparticular a means for anchoring the conduit-guide 1 and thebare-section 7, respectively, within the wall 9 of the heart.

Preferably, but not necessarily, in the bare-section 7 the individualwire 152 is individually coated, what is not the case in the example ofFIG. 4.

The distal wire-end 131 of the conduit-guide according to FIG. 4 isclosed-ended by a welded joint. It is understood that in anotherembodiment the closed-ended of the distal wire-end 131 can accomplishedby a fold of the wire, and/or may include a welded joint end or acoating, especially a polymer coating joining the wire.

FIG. 5 a-5 c show a catheter-sheath-assembly including a conduit-guide 1assembled in a catheter-sheath 8 having a pusher 82 for removing theconduit-guide 1 after having it positioned within the corpus 2 of apatient.

The catheter-sheath-assembly 800 according to FIG. 5 a and 5 b has notbeen introduced into a corpus 2 yet. The conduit-guide 1 ispre-assembled at a diameter D1, D3 into a catheter-sheath 8, wherein thediameter D3 of the conduit-guide 1 assembled in the catheter-sheath 8,my be equal or not equal to the diameter D1, wherein D3 may be inparticular smaller than the diameter D1 of the conduit-guide in theclosed state. In a special embodiment, the catheter-sheath 8 may includea depth-marker, in particular a depth-marker-band for positioning aproximal-end 81 of the catheter-sheath 8 in the corpus 2. The specialembodiment shown in FIG. 5 a-5 c do not include said depth-markers. Thecatheter-sheath 8 according to FIG. 5 a-5 c include, as alreadymentioned, a pusher-device 82 for catheter-sheath 8 removal afterpositioning the conduit-guide 1 within the corpus 2.

Regarding FIG. 5 a, the conduit-guide 1 is completely encompassed by thecatheter-sheath 8 at a diameter D1, D3 and is ready for positioningwithin a corpus 2 of a patient.

FIG. 5 b demonstrates how the pusher-device 82 works. Moving thepusher-device 82 along the arrow P, the catheter-sheath 8 is removedfrom the conduit-guide 1 and the conduit-guide 1 will expand to itsclosed diameter D1, in case that the diameter D3 of the encompassedstate is smaller than the diameter D1 of the conduit-guide 1 in itsclosed state.

Regarding FIG. 5 c, the conduit-guide 1 is introduced into the wall 9 ofthe heart of patient and the catheter-sheath 8 is partly, but notcompletely, removed by the pusher-device 82 from the conduit-guide 1after having positioned the conduit-guide 1 within the wall 9 of theheart.

That is, once the assembly is positioned within the body and the distalend externalized, placement of the conduit-guide would be performed withthe catheter sheath in place. It is envisioned that the catheter wouldbe placed within the body cavity and the distal end tunnelled to emergeout the desired percutaneous site. Once accomplished, the heart (ormajor vessel) would be entered by poking the device through the wall.

It is understood that the invention is not only related to the specialembodiments discussed above but, of course, further embodiments areincluded, too. In particular, the invention relates to all advantageouscombinations of the discussed embodiments.

1. An expandable conduit-guide providing a leak-tight conduit through a skin (3) between an inside of a corpus (2) and an outside of the corpus (2), said conduit-guide (1) including a body (100) encompassing a lumen (110) extending essentially axially along a center-line (120), and having a distal-end (130) to be positioned outside of the corpus (2), and having a proximal-end (140) to be positioned inside of the corpus (2), so that a medical device (4) can be placed in and passed through the lumen (110) between the distal-end (130) and the proximal-end (140) wherein the body (100) of the conduit-guide (1) is constructed from a braided-wire (150) characterized in that the conduit-guide (1) is capable of actively expanding from a closed diameter (D1) to an opened diameter (D2) with the placement of the medical device (4) positioned within the lumen (110) and passively collapsing from the opened diameter (D2) to the closed diameter (D1) upon withdrawal of the medical device (4) under a spring load of the braided-wire (150).
 2. An expandable conduit-guide in accordance with claim 1, wherein a pre-determinable portion of the braided-wire (150) is covered by a flexible membrane (5) enabling the braided-wire (150) to articulate from the closed diameter (D1) to the opened diameter (D2) and the flexible membrane (5) sealing an interstitial space (151) resultant between the braid openings.
 3. An expandable conduit-guide in accordance with claim 1, wherein in the applied state, a pre-determinable velour-portion (6) of the conduit-guide (1) emerging through the skin (3) of the corpus (2), is contained within a velour-like tube (61) to enable a tissue in-growth of the skin (3), in particular to reduce bacterial wicking about the wound and/or the velour material is knitted and/or woven polyester and/or the velour-portion (6) is bonded as a velour-tube (61) to an outside diameter of the conduit-guide (1).
 4. An expandable conduit-guide in accordance with claim 1, wherein the proximal-end (140) of the conduit-guide (1) includes a bare-section (7) which does not contain the flexible membrane (5) in order to permit tissue in-growth about the braided-wire (150), in particular to provide a means for anchoring the conduit-guide (1) and/or the bare-section (7) ranges from 0″ to 0.5″, in particular from 0″ to 0.1″, preferably from 0″ to 0.25″ from a proximal tip of the conduit-guide (1).
 5. An expandable conduit-guide in accordance with claim 1, wherein in the bare-section (7) the individual wire (152) is individually coated.
 6. An expandable conduit-guide in accordance with claim 1, wherein a distal wire-end (131) is closed-ended, in particular closed-ended accomplished by a fold of the wire (152), and/or includes a welded joint end or a coating, especially a polymer coating joining the wire (152).
 7. An expandable conduit-guide in accordance with claim 1, wherein the flexible membrane (5) is fabricated from polyurethane and/or vinyl and/or a thermoplastic rubber and/or a natural rubber and/or a thermoset material, in particular silicone and/or the flexible membrane (5) is dip molded and/or blown film and/or extruded and/or injection molded and/or pultruded and or assembled from flat stock as a separate component and/or assembled to the braided body (100) and/or the flexible membrane (5) is applied about the braided-wire (150) by dipping and/or by coating the braided-wire (150) with liquid polymer and/or the flexible membrane (5) is spray applied to the braided-wire (150).
 8. An expandable conduit-guide in accordance with claim 1, wherein in a un-compressed state a lumen-diameter is between 0.1″ and 1″, in particular between 0.25″ and 0.75″, preferably about 0.5″ and/or wherein the wire is braided to a loose pitch ranging from 0.5″ to 4″, in particular from 0.75″ to 3″, especially from 1″ to 2″ and/or preferably a target length of the wire is 1.5″ pitch for a compressed diameter and/or wherein in a compressed state the lumen-diameter ranges from 0.03″ to 0.15″, in particular from 0.06″ to 0.10″, preferably about 0.08″.
 9. An expandable conduit-guide in accordance with claim 1; wherein the number of wires utilized in the over-under braid ranges from 5 to 100 wires, in particular from 20 to 48 wires, preferably from 24 to 32 wires and/or wherein about half of the wires being left-hand wind and about half of the wires being right-hand wind and/or a wire-diameter of a strand is between 0.001″ to 0.02″, in particular 0.003″ to 0.01, preferably about 0.005″ and/or the wire is made of plastic, and/or made of a composite material, and/or made of a metal, especially made of a stainless steel, preferably made of at least ½ hard stainless steel.
 10. An expandable conduit-guide in accordance with claim 1, wherein the conduit-guide (1) is pre-assembled at a diameter (D1, D3) into a catheter-sheath (8) and/or the catheter-sheath (8) includes a depth-marker, in particular a depth-marker-band for positioning a proximal-end (81) of the catheter-sheath (8) in the corpus (2) and/or the catheter-sheath (8) includes a pusher-device (82) for catheter-sheath (8) removal after positioning the conduit-guide (1) within the corpus (2).
 11. A catheter-sheath for pre-assembling a conduit-guide (1) in accordance with claim
 1. 12. A catheter-sheath in accordance with claim 11, including a pusher (82) for removal the conduit-guide (1) after positioning the conduit-guide (1) within an human or an animal corpus (2) and/or including a depth-marker, in particular a depth-marker-band for positioning a proximal-end (81) of the catheter-sheath (8) in the corpus (2).
 13. A catheter-sheath-assembly including a catheter-sheath (8) in accordance with claim
 11. 14. Method for applying and positioning an expandable conduit-guide (1) made in accordance with claim 1, and for positioning at least one of a catheter-sheath (8) and a catheter-sheath-assembly (800) within a human or an animal corpus (2) including the following steps: providing a conduit-guide (1); positioning a proximal-end (140) of the conduit-guide (1) in a wall (9) of a heart and/or a major vessel; tunneling a distal-end (130) of the conduit-guide (1) through a skin (3) of the corpus (2) to externally communicate a lumen (110) of the conduit-guide (1); and/or including the following steps: providing a conduit-guide (1); tunneling a distal-end (130) of the conduit-guide (1) through a skin (3) of the corpus (2) to externally communicate a lumen (110) of the conduit-guide (1). positioning a proximal-end (140) of the conduit-guide (1) in a wall (9) of a heart and/or a major vessel.
 15. Method in accordance with claim 14, wherein a medical device (4) is placed in and/or passed through the lumen (110) of the conduit-guide (1) and/or the conduit-guide (1) is actively dilated with the passage of the medical device (4) through the lumen (110).
 16. Method in accordance with claim 14, wherein on removing the medical device (4) from the conduit-guide (1), the conduit-guide (1) is collapsed.
 17. Method in accordance with claim 14, wherein the conduit-guide (1) is pre-assembled into a catheter-sheath (8) forming a catheter-sheath-assembly (800).
 18. Method in accordance with claim 14, wherein the catheter-sheath-assembly (800) is placed within a corpus-cavity, a distal-end of the catheter-sheath-assembly (800) is tunneled to emerge out the desired percutaneous site of the corpus (2), a heart and/or an associated vessel, in particular a major vessel is entered by poking the catheter-sheath-assembly (800) and/or the conduit-guide (1) through a wall (9) of the heart and/or the associated vessel and/or a proximal-end (81) of the catheter-sheath-assembly (800) and/or of the conduit-guide (1) is positioned by using a depth-marker, in particular a depth-marker-band, provided about the catheter-sheath (8).
 19. Method in accordance with claim 14, wherein the catheter-sheath (8) includes a pusher-device (82) and the catheter-sheath (8) is removed by the pusher-device (2) once the conduit-guide (1) is positioned within the corpus (2) and/or once the distal-end (130) of the conduit-guide (1) is externalized.
 20. Method in accordance with claim 14, wherein the proximal-end (140) of the conduit-guide (1) is fixed by a suture at a wall (9) of the heart and/or of a associate vessel and/or at a tissue of the corpus (2).
 21. Method in Accordance with claim 14, wherein the medical device (4) is a cannula (4), in particular a cardiac cannula (4) providing a blood conduit between a major blood vessel and/or an external device, in particular an Extracorporal Membrane Oxygenation and/or a Ventricular Assist Device and/or a circuit including a blood pump.
 22. Method in accordance with of claim 14, wherein the medical device (4) is a scope (4) and/or a light (4) and/or a camera (4) and the conduit-guide (1) is provided as a conduit for performing a vision access required for diagnostic and/or therapeutic applications and/or for multi-purpose catheters with vision and/or therapeutic device access.
 23. Method in accordance with claim 14, wherein an access to a kidney, a bladder, a G.I. tract, in particular to an intestine, a stomach, or an esophagus, to a thorax cavity or to a sinus is performed by the guide-conduit (1). 